Field of the Invention
The present invention relates generally to data networks, and more particularly to a network for distribution and load balancing for a virtual service.
Description of the Related Art
Service load balancers, such as server load balancers, application delivery controllers, or traffic managers, typically balance load among a plurality of servers providing network services such as Web documents, voice calls, advertisements, enterprise applications, video streaming services, file transfers, gaming, or any broadband services. A network service is associated typically with an IP address. In a typical IP network, an IP address is assigned to a network computing device. Network routers and switches are designed to forward data packets destined to the IP address to the assigned network computing device. One cannot assign the same IP address to multiple network computing devices with current network routers and switches.
When a service provider deploys a network service, the service provider needs to consider expected client demand that can change between high demand to low demand at different times. In one scenario, a software vendor provides software patches on a regular basis. Normally, a single service load balancer is capable of handling the software patch download demand. However, when the software vendor rolls out a major software update, the software vendor anticipates a dramatic increase of download demand shortly after the major software update is released. The software vendor may plan to add additional resources, such as two additional service load balancers and four more patch servers to handle the increased demand. The software vendor could use different IP addresses for the additional service load balancers. However, this would require the client devices to learn the new IP addresses before requesting the software update service.
The day after the major software update release, the software vendor may see a substantial decline of demand. The software vendor may remove the two added service load balancers and four patch servers. By doing so, the client devices which earlier learned the new IP addresses of the now-removed service load balancers can no longer use the patch service. The client devices must reacquire the IP address of the remaining service load balancer in order to use the software patch service going forward.
During the software update release, the software vendor may have a number of major customers, some of whom require sessions to be encrypted and some of whom require dedicated service load balancers. Some of the added service load balancers may be configured with large memory and processing capacity to handle large bursts of requests. Moreover, some service load balancers may be equipped with special hardware processing capabilities to handle certain services. Such hardware processing capabilities may include, but are not limited to, security processors, special digital signal processors (DSP), network processors (NP), and graphics or video processors. Additional hardware capacity, such as larger memory module, higher performance processor, multi-core processors, and better hardware system design, also affects capabilities of each service load balancer. Special software, such as content caching algorithm or encryption algorithm, may differentiate one service load balancer from another. Furthermore, differentiation of service load balancers may depend on the clients of the service sessions. For example, when access to a government service comes from certain foreign client computers, the sessions may be best served by service load balancers equipped with additional security safeguards. Another example is when access of a company document services is within the company's computers, the accesses may be recorded by specific service load balancers in order to satisfy company regulation or legal compliance.
It should be apparent from the foregoing that there is a need to provide a dynamic service network to distribute service sessions to a plurality of service load balancers according to the capacities and capabilities of the service load balancers or to satisfy particular needs of the clients of the service network.